Zeolite supported ruthenium catalysts are known (Coughlin et al, J. of Catalysts, 49, pp. 97-108, 1977). The ruthenium is reduced to the free-metal state by contacting with H.sub.2 for six hours at 713.degree. K. prior to use as a hydrogenation catalyst.
Kruse et al U.S. Pat. No. 3,963,788 reports the hydrogenation of carbohydrate using a zeolite-ruthenium catalyst. The ruthenium is in the form of the free-metal.
Zeolite Group VIII metal catalysts have also been reported as useful in refinery operations. The ruthenium is generally reduced or modified by other means such as by reaction with H.sub.2 S.